Drive unit of electric vehicle

Abstract

A drive unit ( 54 ) for an electric motor-operated vehicle is provided with a planetary gear mechanism ( 58 ) having; a sun gear ( 58 a ) rotating together with a motor output shaft ( 57 a ), a planetary gear ( 58 b ) meshing the sun gear ( 58 a ), and a ring gear ( 58 c ) meshing the planetary gear ( 58 b ); and constituted that an arm plate ( 58 d ) supporting the planetary gear ( 58 b ) is rotated with the rotation of the motor ( 57 ) at a specified speed reduction ratio. The ring gear ( 58 c ) is supported for rotation relative to a housing and a switching mechanism ( 65 ) is provided to hold or release the relative rotation of the ring gear ( 58 c ).

1. An electric motor-operated vehicle comprised of a frame, a pair of wheels journalled by said frame, a pair of electric motors carried by said frame and each having an output shaft, and a pair of transmissions for selectively driving a respective of said wheels from the respective one of said electric motor output shafts or permitting said wheel to free wheel relative to said output shaft, each of said transmissions comprising a planetary gear mechanism, said planetary gear mechanism having a sun gear element, at least one planetary gear element meshing with said sun gear element, a ring gear element meshing with said planetary gear element and a carrier plate element supporting planetary gear element for rotation, said output shaft being in continuous driving relationship with one of said planetary gear mechanism elements, another of said planetary gear mechanism elements being in continuous driving relation with the respective one of said wheels, each of said transmissions comprising a coupling element that selectively retains the associated ring gear element against rotation or permitting rotation thereof for selectively driving the associated wheel from said output shaft of the respective of said motors at a speed reduction ratio or permitting freewheeling of said wheel relative to said output shaft and an operation mechanism mounted on the vehicle frame, and a transmitting system for transmitting the action of the operation mechanism simultaneously to both coupling elements of said planetary gear mechanisms. 
   
   
     2. An electric motor-operated vehicle according to  claim 1 , wherein the output shaft drives the sun gear element. 
   
   
     3. An electric motor-operated vehicle according to  claim 2 , wherein the carrier plate element is in driving relation with the wheel. 
   
   
     4. An electric motor-operated vehicle according to  claim 3 , wherein the wheel is driven by a transmission output shaft connected to the carrier plate element coaxially with the axis of said plate element, a wheel gear fixed to an inside cylindrical surface of said wheel driven by an output gear formed on the transmission output shaft, the motor output shaft and the transmission output shaft are disposed coaxially. 
   
   
     5. An electric motor-operated vehicle according to  claim 1 , wherein each wheel is journalled on a stationary part of the vehicle in which the respective ring gear is also journalled, each of said ring gears having at least one locking detent opening juxtaposed to said vehicle stationary part forming a part of the coupling element of the respective wheel, each of said coupling elements further including a respective locking pin reciprocally supported in said vehicle stationary part and adapted to engage said locking detent opening of the associated wheel for restraining said ring gear from rotation for effecting a driving relation between the respective electric motor output shaft and wheel, said locking pins being actuated by a common operator. 
   
   
     6. An electric motor-operated vehicle according to  claim 5 , wherein the common operator actuates the locking pins through a respective one of a pair of wire transmitters. 
   
   
     7. An electric motor-operated vehicle according to  claim 1 , wherein each wheel is journalled on a stationary part of the vehicle in which the associated ring gear is also journalled, each of said ring gears having at least one locking detent opening juxtaposed to said vehicle stationary part forming a part of the respective of said coupling elements, said coupling elements further including a locking pin reciprocally supported in said vehicle stationary part and adapted to engage said locking detent opening for restraining said ring gear from rotation for effecting a driving relation between the electric motor output shaft and said wheel.